Modules and Visibility

Module Path

Calling a Public Function

A module groups related items. pub makes a function callable from outside the module, and module::item names the path.

Program

Play the program to choose a multiplication factor and call a public function through its module path.

module_path.rs 
mod math {
    pub fn scale(value: i32, factor: i32) -> i32 {
        value * factor
    }
}

fn main() {
    let factor = ;
    let result = math::scale(5, factor);
    println!("{result}");
}

mod math {
    pub fn scale(value: i32, factor: i32) -> i32 {
        value * factor
    }
}

fn main() {
    let factor = ;
    let result = math::scale(5, factor);
    println!("{result}");
}

mod math {
    pub fn scale(value: i32, factor: i32) -> i32 {
        value * factor
    }
}

fn main() {
    let factor = ;
    let result = math::scale(5, factor);
    println!("{result}");
}
mod `mod math` defines a nested module.
pub fn `pub fn scale` can be called from outside `math`.
path `math::scale` names the function through the module path.